diff --git a/lib/server/routesHandlers/postResponseHandler.ts b/lib/server/routesHandlers/postResponseHandler.ts
index b6cc9684e..fcbbc3cdd 100644
--- a/lib/server/routesHandlers/postResponseHandler.ts
+++ b/lib/server/routesHandlers/postResponseHandler.ts
@@ -39,7 +39,7 @@ export const handlePostResponse = (req: Request, res: Response) => {
     .on('data', function (data) {
       try {
         logger.trace(
-          { ...logContext, dataLength: data.length },
+          { ...logContext, dataLength: Buffer.byteLength(data, 'utf8') },
           'Received data event',
         );
         let bytesRead = 0;
@@ -52,12 +52,16 @@ export const handlePostResponse = (req: Request, res: Response) => {
           );
         }
 
+        let statusAndHeadersLength = Buffer.byteLength(
+          statusAndHeaders,
+          'utf8',
+        );
         if (
           statusAndHeadersSize > 0 &&
-          statusAndHeaders.length < statusAndHeadersSize
+          statusAndHeadersLength < statusAndHeadersSize
         ) {
           const endPosition = Math.min(
-            bytesRead + statusAndHeadersSize - statusAndHeaders.length,
+            bytesRead + statusAndHeadersSize - statusAndHeadersLength,
             data.length,
           );
           logger.trace(
@@ -66,8 +70,8 @@ export const handlePostResponse = (req: Request, res: Response) => {
           );
           statusAndHeaders += data.toString('utf8', bytesRead, endPosition);
           bytesRead = endPosition;
-
-          if (statusAndHeaders.length === statusAndHeadersSize) {
+          statusAndHeadersLength = Buffer.byteLength(statusAndHeaders, 'utf8');
+          if (statusAndHeadersLength === statusAndHeadersSize) {
             logger.trace(
               { ...logContext, statusAndHeaders },
               'Converting to json',
@@ -92,7 +96,7 @@ export const handlePostResponse = (req: Request, res: Response) => {
             logger.trace(
               {
                 ...logContext,
-                currentSize: statusAndHeaders.length,
+                currentSize: statusAndHeadersLength,
                 expectedSize: statusAndHeadersSize,
               },
               'Was unable to fit all information into a single data object',
diff --git a/test/fixtures/client/filters.json b/test/fixtures/client/filters.json
index fe14659df..60eb673df 100644
--- a/test/fixtures/client/filters.json
+++ b/test/fixtures/client/filters.json
@@ -62,6 +62,12 @@
       "origin": "http://localhost:9000"
     },
 
+    {
+      "path": "/echo-with-unicode",
+      "method": "POST",
+      "origin": "http://localhost:9000"
+    },
+
     {
       "path": "/echo-body/filtered",
       "method": "POST",
diff --git a/test/functional/server-client.test.ts b/test/functional/server-client.test.ts
index 73aec4f2e..5e3025360 100644
--- a/test/functional/server-client.test.ts
+++ b/test/functional/server-client.test.ts
@@ -164,6 +164,22 @@ describe('proxy requests originating from behind the broker server', () => {
     expect(Buffer.from(response.data)).toEqual(body);
     expect(response.headers['x-broker-ws-response']).not.toBeNull();
   });
+
+  it('successfully broker POST with unicode body and header values', async () => {
+    const response = await axiosClient.post(
+      `http://localhost:${bs.port}/broker/${brokerToken}/echo-with-unicode`,
+      { some: { example: 'json' } },
+    );
+    expect(decodeURIComponent(response.headers.test)).toEqual(
+      'Special-Char-碰撞.proj',
+    );
+    expect(response.status).toEqual(200);
+    expect(response.data).toStrictEqual({
+      some: { example: 'json' },
+      test: 'Special-Char-碰撞.proj',
+    });
+  });
+
   it('successfully broker GET', async () => {
     const response = await axiosClient.get(
       `http://localhost:${bs.port}/broker/${brokerToken}/echo-param/xyz`,
diff --git a/test/setup/test-web-server.ts b/test/setup/test-web-server.ts
index 24c5e69a8..cb43e4ac6 100644
--- a/test/setup/test-web-server.ts
+++ b/test/setup/test-web-server.ts
@@ -240,6 +240,21 @@ const applyEchoRoutes = (app: Express) => {
     },
   );
 
+  echoRouter.post(
+    '/echo-with-unicode/:param?',
+    (req: express.Request, resp: express.Response) => {
+      const unicodeValue = 'Special-Char-碰撞.proj';
+      const body = JSON.parse(req.body);
+      body.test = unicodeValue;
+      const contentType = req.get('Content-Type');
+      if (contentType) {
+        resp.type(contentType);
+      }
+      resp.setHeader('test', encodeURIComponent(unicodeValue));
+      resp.send(JSON.stringify(body));
+    },
+  );
+
   // mimics functionality of https://httpbin.org/headers
   echoRouter.get(
     '/echo-headers/httpbin',